18 research outputs found

    The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

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    Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

    Structural and analytical studies of silica accumulations in Equisetum hyemale

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    A comparison of alpha and beta diversity patterns of ferns, bryophytes and macrolichens in tropical montane forests of southern Ecuador

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    We present a first comparison of patterns of alpha and beta diversity of ferns, mosses, liverworts and macrolichens in neotropical montane rainforests, and explore the question whether specific taxa may be used as surrogates for others. In three localities in southern Ecuador, we surveyed terrestrial and epiphytic species assemblages in ridge and slope forests in 28 plots of 400 m² each. The epiphytic habitat was significantly richer in ferns, liverworts, and macrolichens than the terrestrial habitat; mosses, however, were primarily terrestrial. Alpha diversity of ferns and of liverworts was congruent in both habitats. Mosses were similar to ferns and liverworts only in the epiphytic habitat. Macrolichens did not share patterns of alpha diversity with any other group. Beta diversity of ferns, mosses and liverworts (lichens excluded due to low species richness) was similar in the terrestrial habitat, but not in the epiphytic habitat. Our results demonstrate that patterns of alpha diversity of the studied taxa cannot be used to predict patterns of beta diversity. Moreover, diversity patterns observed in epiphytes are different from terrestrial plants. We noted a general coincidence in species patterns of liverworts and ferns. Diversity patterns of macrolichens, in contrast, were completely independent from any other taxonomic group studied
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